1. Field of the Invention
The present invention relates to a thermal marker and, more particularly, to a thermal image identification system utilizing infrared energy.
2. Description of the Related Art
Thermal markers used for identification purposes are known in the art. Such markers have been used for various military and law enforcement applications. Conventional markers utilize a pouch containing chemicals that undergo an exothermic reaction on exposure to air to generate heat, and therefore infrared energy, for a period of time. The markers can be seen with special optical equipment, even under low visibility conditions.
There are a number of shortcomings associated with conventional thermal markers. First, they have a limited operational life. Because the heat is generated by a chemical reaction, the marker is no longer usable once the chemicals have been depleted. At the end of its operational life, the conventional thermal marker is discarded.
Further, use of conventional markers requires active participation by the wearer. A user must open a sealed pouch to expose the marker to air and initiate the heat-generating chemical reaction. For military and law enforcement personnel, this active initiation process may interfere with other activities necessary for self-preservation. Also, under extreme conditions, omission of this task could have catastrophic results.
Further, coordinated thermal signaling among a discrete group of individuals is difficult at best. Because remote activation is not feasible, the markers must be continuously activated, leading to excessive visibility to potential enemies and premature depletion of chemical fuel.
To overcome the drawbacks of the prior art and in accordance with the purpose of the invention, as embodied and broadly described herein, one aspect of the invention provides a thermal image identification system, including an infrared emitting element having a laminate, and a power source electrically communicable with the infrared emitting element. The laminate includes an infrared emitting layer having a first side and a second side, a cover layer associated with the first side, and a backing layer associated with the second side.
In another aspect, the invention provides an infrared emitting layer including a support having a first surface and a second surface, a first plurality of conductive elements disposed on the first surface, and a first layer of electrically conductive heating material disposed on the first plurality of conductive elements.
In another aspect, the invention provides an infrared emitting layer further including a second plurality of conductive elements disposed on the second surface, and a second layer of electrically conductive heating material disposed on the second plurality of conductive elements.
In a further aspect, the invention provides an infrared emitting layer including a support having a first surface and a second surface, and at least one resistive element disposed on the first surface.
According to a still further aspect, the invention provides a first heat insulating layer between the infrared emitting layer and the cover layer, a second heat insulating layer between the infrared emitting layer and the backing layer, and an infrared reflective layer between the second heat insulating layer and the backing layer.
In yet another aspect, the invention provides a plurality of infrared elements arranged contiguously for coordinated operation. According to this aspect of the invention, the infrared emitting elements may be arranged in a one-dimensional or a two-dimensional array.
In a further aspect, the invention provides a controller electrically communicating with the power source and with the plurality of infrared emitting elements. According to another aspect, the controller regulates at least one of an operating mode of the infrared elements, an illumination intensity of the infrared emitting elements, a temperature of the infrared emitting elements, and a voltage of the power source.
In a still further aspect, the invention provides a method of marking a target, the method including providing a thermal image identification system, including an infrared emitting element comprising a laminate, securing the infrared emitting element to a target, and activating the infrared emitting element to generate infrared radiation. The laminate includes an infrared emitting layer having a first side and a second side, a cover layer associated with the first side, a backing layer associated with the second side, and a power source electrically communicable with the infrared emitting element.
Additional advantages of the invention will be set forth in part in the description that follows, and in part will be obvious from the description, or may be learned by practice of the invention. The objects and advantages of the invention will be realized and attained by the elements and combinations particularly pointed out in the appended claims.
It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention, as claimed.